fix: remov default values for eslintPath and prettierPath (#93)

* Removed default values for eslintPath and prettierPath

These values are not required by prettier-eslint-cli itself. They
are only passed to prettier-eslint, and even then, they're optional.
When using npm >3, passing the default value is optional, since
the node_modules directory is flattened, but for npm 2.x, the
default assumptions don't work.

People should be running npm >3 today, but for CI scenarios, npm 2
or downwards can still be used in combination with node 4.x (which
is going to be supported for a long time still).

In any case, not passing a default value seems to align better with
node's require algorithm - it will start where it needs to start
(in this case wherever the prettier-eslint dependency has been
installed), and then mimick find-up's logic.

* Removed superfluous imports

src/parser.js

@@ -1,12 +1,8 @@
 import path from 'path'
-import getLogger from 'loglevel-colored-level-prefix'
-import findUp from 'find-up'
 import yargs from 'yargs'
 import {oneLine, stripIndent} from 'common-tags'
 import arrify from 'arrify'
 
-const logger = getLogger({prefix: 'prettier-eslint-cli'})
-
 const parser = yargs
   .usage(
     stripIndent`
@@ -49,7 +45,6 @@ const parser = yargs
     },
     // allow `--eslint-path` and `--eslintPath`
     'eslint-path': {
-      default: getPathInHostNodeModules('eslint'),
       describe: 'The path to the eslint module to use',
       coerce: coercePath,
     },
@@ -61,7 +56,6 @@ const parser = yargs
     // allow `--prettier-path` and `--prettierPath`
     'prettier-path': {
       describe: 'The path to the prettier module to use',
-      default: getPathInHostNodeModules('prettier'),
       coerce: coercePath,
     },
     ignore: {
@@ -160,23 +154,6 @@ const parser = yargs
 
 export default parser
 
-function getPathInHostNodeModules(module) {
-  logger.debug(`Looking for a local installation of the module "${module}"`)
-  const modulePath = findUp.sync(`node_modules/${module}`)
-
-  if (modulePath) {
-    return modulePath
-  }
-  logger.debug(
-    oneLine`
-      Local installation of "${module}" not found,
-      looking again starting in "${__dirname}"
-    `,
-  )
-
-  return findUp.sync(`node_modules/${module}`, {cwd: __dirname})
-}
-
 function coercePath(input) {
   return path.isAbsolute(input) ? input : path.join(process.cwd(), input)
 }