[WIP] start 1.15 port

reorganize packages to match Fabric version
use util classes from Fabric version

src/main/kotlin/mods/betterfoliage/util/Resources.kt

@@ -0,0 +1,26 @@
+package mods.betterfoliage.util
+
+import net.minecraft.client.Minecraft
+import net.minecraft.resources.IReloadableResourceManager
+import net.minecraft.resources.IResource
+import net.minecraft.resources.IResourceManager
+import net.minecraft.util.ResourceLocation
+
+/** Concise getter for the Minecraft resource manager. */
+val resourceManager: IReloadableResourceManager
+    get() = Minecraft.getInstance().resourceManager as IReloadableResourceManager
+
+/** Append a string to the [ResourceLocation]'s path. */
+operator fun ResourceLocation.plus(str: String) = ResourceLocation(namespace, path + str)
+
+/** Index operator to get a resource. */
+operator fun IResourceManager.get(domain: String, path: String): IResource? = get(ResourceLocation(domain, path))
+/** Index operator to get a resource. */
+operator fun IResourceManager.get(location: ResourceLocation): IResource? = tryDefault(null) { getResource(location) }
+
+/** Get the lines of a text resource. */
+fun IResource.getLines(): List<String> {
+    val result = arrayListOf<String>()
+    inputStream.bufferedReader().useLines { it.forEach { result.add(it) } }
+    return result
+}