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Merge pull request #1479 from samccone/sjs/update-readme

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Update for Readme.md

Updated the number of BIFs to properly reflect the current quantity. The number 25 was relevant 3+ years ago.
Merge pull request #1481 from futekov/patch-1

Update for Readme.md
Add jscoverage as a dev dep
Move test runner out of make

* Make does not come on windows (by default)
* We were doing nothing special with the make file for the tests
* Putting the mocha command inside of npm test is SUPER portable
* Attaching tools like node-debug while running the tests is now as simple as node-debug npm test
Merge pull request #1480 from samccone/sjs/move-test-command

Move test runner out of make
Suppress echoing of some commands in Makefile
Add coercion for pt units
Fixed bug with undefined `filename` on keyframes. Closes #1482
Added a way to escape `\` in a tag name. Fixes #1337
Fixed bug with built-in function calls inside a hash assignment. Closes #1458
Fixed same issue with media expressions
Disable bubbling for `@keyframes`. Fixes #1489
Added support for block-level `@import` and `@require`. Fixes #741
Fixed bug with `*` selector first in the group. Closes #1161
Ignore trailing spaces and comments in the selectors groups. Fixes #1134
Fixed bug with complex selectors in conditionals. Closes #837 and #806
Mixin doesn't parse variable if used in first line of mixin. Fixes #982
Variable is undefined immediately after iterating over an empty list. Fixes #878