chore(release-scripts): split BranchPattern from BranchVersion

The release scripts need the BranchPattern to be of the form: 1.4.* so that
they can match the version using Regex.

The doc gen scripts need a SemVer pattern that will match beta releases.
The convention is that 1.4.x is not satisfied by 1.4.0.beta.0

package.json

@@ -1,6 +1,7 @@
 {
   "name": "angularjs",
-  "branchVersion": "1.4.*",
+  "branchVersion": "^1.4.0-beta.0",
+  "branchPattern": "1.4.*",
   "repository": {
     "type": "git",
     "url": "https://github.com/angular/angular.js.git"

scripts/angular.js/tag-release.sh

@@ -17,7 +17,7 @@ ARG_DEFS=(
 )
 
 function checkVersionNumber() {
-  BRANCH_PATTERN=$(readJsonProp "package.json" "branchVersion")
+  BRANCH_PATTERN=$(readJsonProp "package.json" "branchPattern")
   if [[ $VERSION_NUMBER != $BRANCH_PATTERN ]]; then
     echo "version-number needs to match $BRANCH_PATTERN on this branch"
     usage